At present, in the technical field of liquid crystal display devices, IPS (In Plane Switching) liquid crystal displays and FFS (Fringe Field Switching) liquid crystal displays mainly adopt a transverse electric field mode. An FFS liquid crystal display includes an upper electrode layer and a lower electrode layer insulated from each other through an insulating layer, the lower electrode layer is used as a common electrode layer, the upper electrode layer is used as a pixel electrode layer, and slits and the like are formed in the upper electrode layer and used as apertures for electric fields to pass through. In a transmittance formula T=To sin2 (2Φ) sin2(πdΔn/λ) of the IPS/FFS liquid crystal display, Φ is an inclined angle between a liquid crystal molecule pointing direction and an incident light polarization direction. Under the condition that cell gap, liquid crystal molecules and the like are not changed, when the applied voltage is increased till the applied electric field enables the liquid crystal molecules to averagely deflect 45°, the transmittance T is the maximum.
As shown in FIG. 1 to FIG. 4, in a traditional electrode structure of the FFS liquid crystal display, Ex is an electric field parallel to an end electrode 61, Ey is an electric field parallel to branch electrodes 62, and Ez is an electric field perpendicular to the plane of the Ex and the Ey. Specifically, as shown in FIG. 1 and FIG. 2 (FIG. 2 is a cross-sectional view of a pixel element in FIG. 1 along A-A′), a common electrode 5 is arranged on a lower substrate 1 of the FFS liquid crystal display, a pixel electrode 6 is located on the common electrode 5 and includes an end electrode 61 and a plurality of branch electrodes 62, and the end electrode 61 is configured to connect the plurality of branch electrodes 62. The FFS liquid crystal display includes an upper substrate 2, the lower substrate 1, and a liquid crystal layer 7 sandwiched between the upper substrate 2 and the lower substrate 1. A TFT (Thin Film Transistor) layer 3 is arranged on the lower substrate 1, a first insulating layer 41 covers the TFT layer 3, the common electrode 5 is arranged on the TFT layer 3, a second insulating layer 42 covers the common electrode 5, and the pixel electrode 6 is formed on the second insulating layer 42. As shown in FIG. 2, the end electrode 61 is located at the boundary of the pixel element, and the liquid crystal layer 7 corresponding to the end electrode 61 is located at the boundary of the pixel element. As shown in FIG. 3, the electric field in the Ex direction, which mainly exists on the liquid crystal layer 7 corresponding to the branch electrodes 62, enables the liquid crystal molecules to deflect in an electrode plane, thus avoiding a phenomenon of disclination lines. As shown in FIG. 4, the electric field at the boundary of the pixel element where the end electrode is located causes disordered arrangement of the liquid crystal molecules to generate a dark area, and the deflecting directions of the liquid crystal molecules are opposite to the expected directions, even if the boundary of the pixel element where the end electrode is located is a bright area. Specifically, when a TFT is in an on state, i.e., the TFT is turned on, deflection of the liquid crystal molecule at a position E near the end electrode 61 may be affected by the electric fields in the Ey and Ez directions, so that the electric field at the boundary of the pixel element where the end electrode is located becomes extremely complex, the liquid crystal molecules at the boundary of the pixel element where the end electrode is located are arranged unstably, the deflecting directions of the liquid crystal molecules are inconsistent with the orientations of the liquid crystal molecules at a position F, and the phenomenon of disclination lines occurs to cause non-uniform picture displaying; and the deflecting directions of the liquid crystal molecules in the on state at the position F near the branch electrodes 62 are consistently oriented. As shown in FIG. 5, by using the simulation result of TechWiz LCD optical software, since the electric field at the boundary of the pixel element where the end electrode is located is complex, an area with the phenomenon of disclination lines exists to cause transmittance of the pixel element to decline, and even at the position E and the position F both of which are bright areas, the deflecting directions of the liquid crystal molecules are different. Since the position E is at the boundary of the pixel element where the end electrode is located, the liquid crystal molecules are in the complex electric field and have the deflecting directions opposite to the expected directions. Due to the problem of disclination lines in the prior art, adverse problems of non-uniform picture displaying and the like may be caused.